[mkgmap-dev] motorway_link not always oneway

Tue Oct 26 22:27:27 BST 2010

2010/10/26 Marko Mäkelä <marko.makela at iki.fi>:
> On Tue, Oct 26, 2010 at 10:23:28PM +0200, Martin Simon wrote:
>>-on many motorway_links (that i was aware of) people removed the
>>"unneccessary" oneway=no tags in the following months
>
> Did you consider adding note='this is oneway=no because the default for
> motorway_link is oneway=yes'? :-)

No, and i did nothing to stop the retagging because I didn't want to
start and fight in edit wars over single tags in remote areas that i
never visited... ;-)

> Luckily, the motorway_links haven't been subject to an edit war in
> Finland. There has been some edit war and debate regarding cycleways
> (which IMO should be tagged as highway=path, segregated=yes/no,
> bicycle=designated, foot=designated, moped=yes/no, surface=*,
> lit=yes/no

Amen. :-)

>
> As you can see from the above example, I prefer explicit tagging too. It
> can be a bit overwhelming for beginners, but implied things and country
> defaults are nasty for anything that tries to interpret the map data.

Right, plus, any implied-defaults-list on the wiki can be subject to
editwars itself, which causes more damage than edit wars over single
explicit tags of single objects in our database.

> PS: Any objections if the default style adds surface=paved to motorways
> and motorway links? What does the Vienna convention say about motorways?
> Does it require a paved surface?

No, not from my side. IMHO, there is quite a difference between
"dictating" global or per-country defaults for highway types and
interpreting data when reading it with a tool like mkgmap.

In my own mkgmap style, i also try to make "clever" assumptions wheter
a way is paved or not and the like, based on the main highway tag,
designation, etc.

IMHO, the best thing to happen for the database would be tools like
mkgmap ignoring top level highway tags to some degree (lets say
reducing them internally to
pathlike->tracklike->normalroadlike->connectingroadlike->motorwayroadlike)
and focusing on the secondary, more specific tags like surface, lanes,
width, sac_scale, "grade_seperated" etc. to determine the
sub-categories and routing importance.

-Martin